Kaspersky Hacked

I changed to Kaspersky a few years ago because of recommendations from different people including my computer support centre. this year i have twice been hacked by a trojan that has infected my emails & on the other occasion my wife lost all the info on her hard drive. Apparantly Kaspersky had been disabled to allow the intrusion. How is this allowed to happen ? I will be moving immediately inspite of still having more than half a years subs left.